Argentine Ants Small But Invasive

News Release Distributed 10/14/04

They look like little tiny nomads, constantly on the move. They are hunters in search of water and something sweet, and, once an Argentine ant finds a food source, you can bet she will let her colony know about it.

These sugar ants are a fairly new species to Louisiana, according to LSU AgCenter experts, who say the ants are small and do not sting, but they are invasive.

Argentine ants have become a big problem in the Toledo Bend area, and they are being found around the state.

"Typically we find them trailing up trees," said LSU AgCenter entomologist Patricia Beckley. "What they are doing is feeding on the honey dew which is produced by the aphids and scale insects that are up in the trees."

The ants may be typical in trees, but the experts say it is not unusual to find them in homes, as well. And when they get in, it is hard to them out.

Earlier this year Baton Rouge area homeowner Joan Payne noticed a trail of ants in her house.

"They were in the bathroom in my shower and sinks," Payne said. "I saw a trail of ants leading from the shower into the siding of the home."

She sprayed the trails and hired a contractor to fix a problem under her house, but the ants just moved to a new area.

"I started finding some in the kitchen and the cabinets and continued to spray, and that did not relieve the problem."

Instead of spraying, Beckley said homeowners need to offer the ants poisonous bait that they can bring back to their nest and feed to the colony.

One problem is if the ants are happy with what they are eating, like the honeydew in the trees, they won’t go to the bait stations.

To combat that problem, homeowners can band trees to stop the ants from trailing up the trees, according to Beckley.

"Saturate a band of a cotton absorbent with pesticide, and it will kill them as they are going up and down." Beckley said. "Then the ants remaining on the ground will go to the bait."

Homeowners can purchase bait at a hardware store or make their own with boric acid and sugar water. The baits should be placed inside the home where ants appear or outside near trees.

One of the reasons Argentine ants are so hard to control is that they aren’t like fire ant colonies, which have only one queen. Argentines have several queens that can establish new colonies.

"Ten percent of the colony is queens, and they move with the rest of the ants." Beckley explained.

Since they can trail from a tree onto a house, Beckley recommends that homeowners trim any branches that may be touching a home.

Argentine ants are aggressive to other insects – but not to other Argentine ant colonies. They can form super colonies like one in Australia that stretches for 62 miles, Beckley cautioned.